Graphophone.



s. E. woous.

GRAPHOPHONE v APPLICAIION FILED MM?- 8, 1915. I 1,210,248. Patented Dec. 26,1916.

a snares earner orrion.

oni-Enron 'n'w'oons, or iznrnenroair; communicate; Assrenonro AME I AN casino- PHONE CGMPANY, or simnenronr, connncrieo'r, A oonronarron or waste cnarnornon'n.

Specification of Letters-ream.

Patented Dec. 26, 1916.

Application filed March 8, E915. Serial No. 12,845.

To all whom it may concern:

Be it known that I, Cmn'ron E. Woo'ns, a citizen of the United States, and resident of Bridgeport, Fairfield county, Connecticut, (whose post-oflice address iscare of American Graphophone 00., Bridgeport, Connecticut,) have invented a new and useful Improvement in Graphophones, which inventionis fully set forth in the following specification.

The invention relates particularly to machines of the type known as polyphones, wherein two or more styli track tandem in the same record-groove.

The object of the present invention is to utilize the polyphone principle in such novel manner, in increasing the volume and in improving the quality of the reproductions obtained by the graphophone or other talkingmachine, as to avoid sacrificing the accuracy of definition.

The invention is primarily applicable for use wit-h records of the disk form having thereon a spirally-disposed record-groove of the laterally-undulating or zigzag type, although the invention may be applied to othertypes of record upon other forms of tablet.

One feature of the invention consists in pivoting the two or more independentstylussupporting arms (preferably tone-arms) upon independent axes located at equal dis-'- tances from the centeror axis of the rotary sound-record.

Another feature of the invention consists in locating the several styli at equal distances from the axes of their respective supporting passagcs leading from the respective tonearms to the outer air,

A fourth feature of the invention is brought into play only when the styli are out of engagement with the record, and consists of novel means for attairingthe proper -relataneously with a disk-tablet containing a spirally-disposed record-groove of the zig-,

zag type.

In the (of the inclosed-horn type) embodying one form of the invention; and Figs. 2 and 3 are details, in end and side view respectively, of

the structure shown in Fig. 1.

In this particular embodiment, 1 represents a disk or flat tablet containing a spirally-disposed record-groove of the zigzag type, and carried by the usual turn-table, whose center post provides the-axis of rotation or center 2. i

3 indicates the inner (or left hand) one of the twotone-arms, of the usualor anydesired construction, and journaled in the usual 'rnanner, or as'in U. S. Patent No.

1,108,302, so as to swing vertically and also to swing horizontally over the face of the record, upon the fixed axis 4, and carrying at its free end the usual sound-box 5. At-

drawings, Figure '1 isa plan view, indicating a portion of a. talking-machine the outer end is an elbow, so that the vertical diaphragm of this sound-box lies to one side (the right) of the main portion of the arm; and upon its face or outer side (at the right) is the usual stylus-bar, connected at its inner end. to the face of the diaphragm and at its outer end carrying the stylus or needle 6, projecting forwardly and downwardly for engaging the spiral record-groove. Preferably, the distance from the operative tip of the stylus 6 to its axis 4: is equal to the distance between said axis 4: and the center 2. 7 representsthe second tone-arm,of similar preferably equal to the distance from center construction, and similarly journaled upon its own fixed axis 8 located to one side of axis 4, andat the same distance from the center 2. This second tone-arm carries its own independent sound-box 9, offset to the left so as to lie as near as convenient to the first-named sound-box, and carrying its own stylus 10. The distance between stylus 10 and its axis 8, is the same as the distance between stylus 6 and its axis 4;, each being are thus presented, tandem within the same convolution of the record-groove, and equidistant from their respective axes, and'with said axes equidistant from center '2. The two diaphragms need not face the same way, nor need they be located substantially abreast of each other; but the best results are obtained by locating them substantially abreast and facing each other, in parallel relation, as shown. It is well known thatin making these spiral record-grooves in the first instance, the tablet is rotated at a uniform axial speed, so that the surface-speed decreases in proportion to the approach toward the center or axis of the rotating disk; and, as a consequence, given sounds recorded near the periphery will occupy greater length of groove than if recorded nearer the axis of the disk; or, put another way, the record of a given sound-wave nearer the edge of the disk is longer than the record of the same wave nearer the center of the disk. Geometrically stated, the groovelength occupied by a given sound-wave depends directly upon its distance radially from the center of the rotating recorddisk.

Referring, now, to Fig. 1, the two arms 46 and. 810 are made of equal length, their two axes 4 and 8 are located that same distance from the axis or center 2- of the rotating record, and the two styli 6 and 10 are fed by the spiral record-groove so as to be at all times (practically) equidistant from said center 2; hence the two styli at all times subtend the same angle from the center 2 (the same as the angle 4E2-8); and that means that the distance between the two styli just like the groove-length of a given sound-wave-depends directly upon their common istance from said center 2..

In short, with :espect to the recorded soundwaves, the two styli are at all times the same relative distance apart. It is to be understood, of course, that more or less departure from the exact equalities of distance above referred to, will not be a departurefrom the invention.

In the preferred form of the invention,

to play the record. A preferred device of the character is illustrated in the drawings, in which 11 represents a lateral bracket extending rigidly from one of the two arms, as 3, and carrying at its outer end the depending roller or stud l2. Beneath the other arnnl is secured a plate 13 having the curved cam-groove which loosely receives the stud 12. A grippingarm 14: is pivotally secured upon the cam-plate 13, and at its outer end is provided with the thumb-plate 15, and normally held retracted by a spring 16.

In starting to play a record, the operator lifts the outer end or elbow of the outer tone-arm 7, in the usual manner for positioning the ordinary single sound-box and. stylus, whereby the other sound-box is also lifted, but the tip of its stylus will then hang down somewhat lower than the tip of the outer stylusv 10; next, he swings the two arms outward, above the beginning of the record-groove, and then presses agamst thumb-plate 15, which brings the two styli into approximate alinement; next, he gently lowers. the two arms until the lower (and inner) stylus 6 engages the desired recordgroove; and, thereafter, he moves the other stylus 10 into proper alinement while low-- ering it into the same groove. As soon as this second stylus, 10, is seated, the thumbplate is at once released, and the spring 16 instantly retracts the arm 14, thus leaving room for whatever lateral play of stud 12 may be required bythe two styli in properly tracking the record-groove.

The proper curve of the cam-wall can be easily 'plotted, as by securing a blank beneath arm 7, carefully positioning the two independently-swinging styli in the outer convolution of the rotated record-groove, and then starting the machine and tracing upon said blank the path of the stud 12.

If desired the gripping-arm can be omitted; indeed, the entire outer limb of plate 13 (which serves as the left-hand Wall inclosing the slot) can be omitted,there being retained only the cam-face that constitutes the right-hand wall of the slot. And, indeed, the connecting-devices 1112 and 13 can be entirely dispensed with and the two tone-arms positioned by hand.

1717 represents the stationary soundconveyer or concealed horn leading from tone-arm 3 to the outer air; while 18-18 represents a similar passageway leading innemesis dependently from the other tone-arm to the outer air; The reproduction seems more pressing when there are thus two entirely separate passages; but, if desired, there may be a-single sound-emitting passageway with which both tone-arms communicate. 0 if desired, the tone-arms may communicate with one visible born, or separately with two such horns.

In the foregoing description, with the annexed drawings, is set forth merely one is claimed is: i

- 1. The combination, in a talking-machine,

of a turn-table, two arms pivotedon separate axes at equal distances from' the center of said turn-table to swing freely over the same, and a stylus carried by each arm at that same distance from its axis.

2. The combination, in a talking-machine,

of a turn-table, a plurality of independent arms mounted upon vertical axes located adj acent each other and on the same side of the turn-table, whereby said arms can swing freely in a horizontal plane, a stylus carried by each arm equidistant from the axis there of, and said axes being equidistant from the center of said turn-table, whereby said styli can be propelled in continuously-converging paths.

3. The combination, in a talking-machine, of a turn-table, a plurality of rigid arms pivoted upon separate axes located adjacent each other on the same side-of the turn-table and equidistant from'the center of said turntable, and an independent sound-box and stylus carried upon each arm and adapted to be propelled in continuously-converging paths as well as vibrated by a record-groove carried by said turn-table.

4. The combination, in a talking-machine, of a turn-table, a plurality of freely-swinging arms each pivoted separately on a fixed axis, said axes being'located adjacent each other on the same side of the turn-table, and a stylus on the free end of each arm equidistant from the axis thereof, said styli adapted to simultaneously, engage a recordg'robre carried by said turn-table and to be propelled in continuously-converging paths as Well as vibrated thereby.

5. The combination, in a talking-machine,

of a disk-record and a plurality of independent sound-boxes swinging upon separate axes that are located adjacent each other on the same side of the disk and equidistant from the center of said disln'whereby the styliof said sound-boxesare propelled in continueusly-converging paths.

6. The combination, with a rotary tablet carrying a spirally-disposed record-groove, of two styli mounted to be vibrated and pro polled by said rotating groove and at all times spaced from each other by the same relative distance with respect to the recorded undulations corresponding to the sound-waves.

7. The combination, in a talking-machine, of a turn-table carrying a spirally-disposed record-groove, and a plurality of styli mounted to be fed simultaneously in continuously-converging paths across said tablet by said groove.

8. The combination, in a talking-machine, of a swinging-arm carrying a stud rigidly secured thereto, a sound-box on the end of said arm, a second swinging-arm carrying a member rigidly secured thereto having a groove for engaging said stud, and a second sound-box on the end of the second arm aforesaid. I

9. In a talking-machine adapted to carry a rotary tablet having a spirally-disposed record-groove, a plurality of sound-boxes independently mounted to travel across said the same convolution of said grooves, whereby they can be propelled simultaneously across said tablet by said rotating spiral groove while being vibrated by the irregularities thereof. I

10. The combination, in a talking-niachine, of two independently-mounted swinging-arms, a sound-box with its stylus on the free end of each arm, and a self-adjusting mechanical connection for said arms consist ing of a bearing-surface carried rigidly by one arm and a co-acting abutting-mei'nber carried rigidly by the other.

-11. The combination, in a talking-ma chine, of a plurality of independentlymounted swinging-arms each carrying a sound-box and stylus at its free end, and coacting members carried rigidly on said arms forobtaining. proper alinement of said styli.

12.'The combination, in a talking-ma chine, of arotary tablet containing a spirally-disposed record-groove, a plurality of independently-mounted and horizontallyswlnging sound-conveying members pivoted adjacent each other on the same side of said tablet, a separatestationary sound-passage leading from each member to the outer air, and a sound-box on the free end of each swinging-member aforesaid with the respective styli thereof simultaneously engaging said record-groove, whereby said styli can be propelled in continuously-converging paths.

13. The combination, in a talking-machine, of a rotary tablet containing a spirally-disposed record-groove, a plurality of inclepenolently-mounted and horizontallyswinging sound-conveying members, a separate stationary sound-passage leading from each member to the outer air, a sound-box on the free end of each swinging-member ing Witnesses.

' CLINTON E. WOODS;

Witnesses:

LAURETTA T. NEAL,

FRANK G. HINCKLEY. 

